1. Field of the Invention
This invention generally relates to a movement detection device that identifies three-dimensional motions of an object with a light source in combination with a plurality of light sensing elements.
2. Description of the Related Art
Current movement detection devices can only detect the movement substantially parallel to the movement detection device. For example, conventionally there is a cell phone including a movement detection device. If the cell phone is placed on a plane defined as an XY plane, the movement detection device of the cell phone can only detect an object moving along X and Y directions, e.g. a waving gesture along a direction substantially parallel to the cell phone. It is because that the sensor integrated in current movement detection devices is mainly for detecting whether an object blocks the sensor or not, and generally a plurality of sensors are integrated in a movement detection device to identify a moving direction of the object by detecting whether the movement of the object blocks the sensors and by recognizing a sequence that the plurality of sensors being blocked during operation. This kind of movement detection device is designed for detecting movements on a predetermined plane. For an object moving along a direction perpendicular to the predetermined plane (e.g. a Z-direction perpendicular to the XY plane), as the movement of the object does not change the projection of the object on the movement detection device, the conventional movement detection device can not effectively detect the motion of the object along a direction perpendicular to the predetermined plane.
Accordingly, a movement detection device that can simultaneously detect three-dimensional motions in a space range is required by the art.